How Alcohol Affects the Immune System

Alcohol affects the immune system in a negative way, like so many other problems caused by its consumption. What's more, you don't have to be chronically addicted in order to suffer from complications.
How Alcohol Affects the Immune System

Last update: 11 August, 2021

Recommendations regarding how alcohol affects the immune system have oscillated in medical science between a glass of wine to raise the defenses to its total prohibition. This led to intense debates and a series of investigations to clarify the issue. Needless to say, alcoholism is a prevalent vice with disastrous consequences. It’s an addiction that’s present in all ages of life and every area of our planet.

The immune system isn’t exempt from the effects of alcohol, and it’s important for people to understand this, so that they don’t fall into misunderstandings. Sometimes, due to commercial eagerness, some brands promote unhealthy consumption.

The negative side of alcohol doesn’t only manifest itself in the long term or in those who are chronic consumers. We know that this drug is behind traffic accidents, domestic problems, and injuries caused by fights. But that’s not all. Acute and excessive consumption of alcohol affects the immune system in a harmful way, slowing down healing processes, for example.

By knowing how alcohol affects the immune system, we take a step forward in the possibility of lessening the effects of this addiction. In addition, we’ll discuss elements regarding the treatment of specific cases where alcoholism favors infections and even the development of neoplasms.

Where do we see the effects of alcohol on the immune system?

The first point of contact of alcohol with the body is the digestive system. Primarily, the mucous membranes of the mouth, stomach, and intestine. The latter is a key part of the immune system in order to stop diseases.

In the intestinal mucosa, the internal lining functions as a barrier so that harmful substances don’t enter the blood. Alcohol is capable of irritating this mucosa and creating small openings through which microorganisms can filter.

Also, in the gastrointestinal system, we have the microbiota, that set of bacteria that inhabit the intestine and behave collaboratively with the human being, without making them sick. Alcohol, when it enters the intestinal tract, alters the balance of these microorganisms and diminishes their natural defensive function.

And it’s not only the gastrointestinal section that’s affected, but also the respiratory system. The lungs have mechanisms to collect mucus and expel microbes to the outside with the movement of small hairs called cilia.

It turns out that alcohol affects the pulmonary immune system by disrupting the movement of the cilia. Not to mention that the white blood cells near the bronchi become less efficient in cases of alcoholism.

The microbiota of the intestine.
Alcohol alters the balance of the intestinal microbiota, which allows pathogens to enter.

Continue reading: The Effects of Alcohol on the Heart

Phases of alcohol-induced immune involvement

Alcohol affects the immune system in three distinct temporal phases, from immediate to indirect chronic. These periods follow one another and even overlap in an alcoholic person.

In the acute phase, the body’s defense cells tend to attack alcohol as an external, unrecognized toxic substance. Then, when there’s an immune response, there’s inflammation; the problem is that alcohol is able to block certain inflammatory proteins.

The inflammatory blockade by alcohol is complex, but we know that we can easily see two direct effects. First, epithelia heal more slowly and, second, infections penetrate more easily, especially at the pulmonary level.

As time goes by, if we continue to consume alcohol in excessive quantities, the white blood cells are increasingly blocked by the drug. We acquire chronic impairment of the immune system and the possibility of opportunistic infections taking over our organs.

Lastly, there are the indirect effects, that is, those derived from the hormonal and metabolic changes caused by alcohol. The substance is capable of modifying the circadian rhythm and damaging the liver, where multiple hormones are metabolized.

Friends toasting with alcohol.
The consumption of alcoholic beverages causes a weakening of the immune system that ranges from acute to chronic.

There’s no safe dose of alcohol for the immune system

As far as the immune system is concerned, we can say that science hasn’t found an amount of alcohol consumption that we can consider safe in its entirety. It’s essential to be clear about this so as not to fall into commercial deceptions.

Alcoholism is a public health problem, and young people are the most vulnerable population at risk. If a person starts problem drinking in adolescence, they’re likely to suffer from serious immunity problems in early adulthood.

To conclude, prevention is the best way to address the situation, and information becomes a key tool. Therefore, the more we know about what science has discovered about how alcohol affects the immune system, the more aware we’ll be about alcohol consumption.

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